htils 1
A small set of utilities for C programming.
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Data Structures | Macros | Typedefs | Functions
darray.h File Reference
#include <htils/arena.h>
#include <htils/assert.h>
#include <htils/basictypes.h>

Go to the source code of this file.

Data Structures

struct  da_header
 The header of a dynamic array. More...
 

Macros

#define DA_HEADER_SIZE
 
#define da_len(darray)   ((darray) ? da__hdr(darray)->len : 0)
 
#define da_cap(darray)   ((darray) ? da__hdr(darray)->cap : 0)
 
#define da_new(arena, darray, intitial_capacity)
 Initialize a dynamic array.
 
#define da_append(arena, darray, item)
 Append an item to a dynamic array.
 
#define da_pop(darray)
 Pop an item from a dynamic array.
 
#define da_last(darray)    (htils_assert(da__hdr(darray)->len > 0), (darray)[da__hdr(darray)->len - 1])
 Substitute with the last item in a dynamic array.
 
#define da_clear(darray)
 Clears a dynamic array.
 

Typedefs

typedef struct da_header da_header_t
 The header of a dynamic array.
 

Functions

static da_header_t * da__hdr (void *da)
 Get the da_header.
 

Macro Definition Documentation

◆ da_append

#define da_append (   arena,
  darray,
  item 
)
Value:
do { \
htils_assert(arena != null && "Arena cannot be null."); \
htils_assert(darray != null && "Darray cannot be null."); \
htils_assert(item != null && "Item cannot be null."); \
\
if (!(darray) || da__hdr(darray)->len >= da__hdr(darray)->cap) { \
u64 old_capacity = da__hdr(darray)->cap; \
u64 new_capacity = old_capacity ? old_capacity * 2 : 8; \
u64 old_len = da__hdr(darray)->len; \
u64 alloc_size = DA_HEADER_SIZE + new_capacity; \
\
da_header_t *header = arena_alloc((arena), darray, alloc_size); \
\
header->cap = new_capacity; \
header->len = old_len; \
\
if (darray) \
memcpy(header + 1, (darray), old_len * sizeof(*(darray))); \
\
(darray) = (void *)(header + 1); \
} \
\
(darray)[da__hdr(darray)->len++] = (item); \
} while (0)
arena_alloc
#define arena_alloc(arena, type, size)
Allocate a chunk of memory from the arena.
Definition arena.h:167
u64
uint64_t u64
Definition basictypes.h:17
null
#define null
Definition basictypes.h:47
DA_HEADER_SIZE
#define DA_HEADER_SIZE
Definition darray.h:24
da__hdr
static da_header_t * da__hdr(void *da)
Get the da_header.
Definition darray.h:44
arena
An arena.
Definition arena.h:26
da_header
The header of a dynamic array.
Definition darray.h:14
da_header::len
u64 len
Definition darray.h:16
da_header::cap
u64 cap
Definition darray.h:15

Append an item to a dynamic array.

By incrementing the len, has automatic capacity growing functionality through extra allocations with arena_alloc().

Parameters
arenaThe arena to allocate the dynamic array from.
darrayThe dynamic array to append to.
itemThe item to append to the dynamic array.
Precondition
arena, darray, and item must be valid and cannot be null.
See also
arena_alloc()

◆ da_cap

#define da_cap (   darray)    ((darray) ? da__hdr(darray)->cap : 0)

Gets the capacity of the current dynamic array

◆ da_clear

#define da_clear (   darray)
Value:
do { \
if (darray) \
da__hdr(darray)->len = 0; \
} while (0)

Clears a dynamic array.

By setting its length to 0, if the dynamic array is null, nothing happens.

Parameters
darrayThe dynamic array to clear.

◆ DA_HEADER_SIZE

#define DA_HEADER_SIZE
Value:
((sizeof(da_header_t) + _Alignof(max_align_t) - 1) & \
~(_Alignof(max_align_t) - 1))
da_header_t
struct da_header da_header_t
The header of a dynamic array.

The size of the header of a dynamic array.

◆ da_last

#define da_last (   darray)     (htils_assert(da__hdr(darray)->len > 0), (darray)[da__hdr(darray)->len - 1])

Substitute with the last item in a dynamic array.

Asserts that the length of the dynamic array is larger than 0, then simply gets the last entry.

Parameters
darrayThe dynamic array to get the last item from.

◆ da_len

#define da_len (   darray)    ((darray) ? da__hdr(darray)->len : 0)

Gets the length of the current dynamic array

◆ da_new

#define da_new (   arena,
  darray,
  intitial_capacity 
)
Value:
do { \
htils_assert(arena != null && "Arena cannot be null."); \
htils_assert(intitial_capacity > 0 && \
"Initial capacity must be greater than 0"); \
\
u64 capacity = (intitial_capacity); \
u64 alloc_size = DA_HEADER_SIZE + capacity; \
\
da_header_t *header = arena_alloc((arena), darray, alloc_size); \
header->cap = capacity; \
(darray) = (void *)(header + 1); \
} while (0)

Initialize a dynamic array.

Caluclates the size for the header with DA_HEADER_SIZE, and the capacity; Allocates the header with initial_capacity, using arena_alloc(), then sets the dynamic array to be the header + 1 offsetting the header.

Parameters
arenaThe arena to allocate the dynamic array from.
darrayThe dynamic array to initialize.
intitial_capacityThe initial capacity of the dynamic array.
Precondition
  • arena, and darray must be valid and cannot be null.
  • intitial_capacity must be greater than 0.
See also
arena_alloc()

◆ da_pop

#define da_pop (   darray)
Value:
do { \
if (darray && da__hdr(darray)->len > 0) \
da__hdr(darray)->len--; \
} while (0)

Pop an item from a dynamic array.

By simply decrementing its length, if the dynamic array is empty, nothing happens.

Parameters
darrayThe dynamic array to pop from.

Typedef Documentation

◆ da_header_t

typedef struct da_header da_header_t

The header of a dynamic array.

Parameters
capThe capacity of the dynamic array.
lenThe length of the dynamic array.

Function Documentation

◆ da__hdr()

static da_header_t * da__hdr ( void *  da)
inlinestatic

Get the da_header.

Casts the da to cstr * from a dynamic array, by then offsetting by the size of it.

Parameters
daThe dynamic array to get the header from.
Precondition
da must be valid and cannot be null.
Returns
The da_header of the dynamic array.